Secondary Storage is just a NFS share. If you want to expose that, to the world, you will need to open up the appropriate ports on you firewall(s). You can search for "NFS firewall rules" to figure out the ports needed. It would also be possible to expose the same files via HTTP, but remember that snapshots are also stored in Secondary Storage. Be very careful about what is exposed to whom.

The Secondary Storage VM (SSVM) is the small Debian-based VM that CCP spins up to expose Secondary Storage into the cloud. The SSVM should be able to reach the Internet, assuming networking is working correctly. I can't think of any services provided by the SSVM to would provide any value to folks outside the cloud.

--Mike